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By D. E. Keeley

lntroduction Some years ago it was general practice in Canadian mines to use the best timber available, just as it was cut from the tree. Later, to prevent 'borers' from getting into the wood while stacked in the yard, the bark was peeled off, cleaned up carefully, and burned to eliminate a breeding ground for these and other destructive insects. This practice of good housekeeping also decreased the hazard from fire in scattered bark. A few years after damage by borers had been minimized, it became apparent that increased temperatures in the mines, occasioned by deepening operations, were being accompanied by rapid growth of fungus and by decay in timber underground, greatly shortening its life. In places on upper levels where the air temperature was below 50 deg. F., untreated timber retained a large proportion of its strength for ten or more years. In other places on these levels, however; its life was short and it developed much dry rot and merulius lacrymans. In these latter places and on lower levels in the mine where temperatures ranged from 50 to 60 deg. F., approximately, the wood became infested with extensive growths of this white fungus. This development was accompanied by the production of millions of spores. Spread of infection was due mainly to the transfer of spores from the warm lower levels to the cool upper horizons by upcasting ventilation currents. So serious did this become that about twenty years ago Lake Shore, Hollinger, and McIntyre Mines decided to investigate the use of wood preservatives and the plant necessary to treat timber.

Jan 1, 1949

By L. M. English

In the past 30 years, the research arena has changed significantly in all fields, mining included. The relative representation of the topics of research, how the research is performed, and who has performed the research have all changed significantly over these decades. Although there are a lot of subjective ideas concerning these changes, and there is a fair amount of anecdotal "analysis," there has been no actual study of these trends to verify the facts. The period studied is divided into six five-year periods for the purposes of comparison. Some of the trends analyzed are as follows: ? Co-authorship ? Research areas ? Research sponsors ? Cooperative efforts

Jan 1, 1995

By Scott W. Hazen, Richard F. Link, George S. Koch

The Mi Vida mine , Big Indian district , San Juan County , Utah , is in an ore deposit of uranium and vanadium minerals disseminated in certain sedimentary beds of the Triassic Chinle formation . Statistical analysis of assays of samples taken from the ore body affords an estimate of the grade of the ore body and provides a prediction about the direction of best mineralization beyond the sampled area . The basic data analyzed are assay results for uranium ( Uз Og ) , vanadium (V₂O ) , and lime (CaO ) from 225 channel samples cut at 79 sample points . Through the use of appropriate statistical methods , particularly regression analysis , the grade of ore may be estimated more precisely than by conventional means , and the most favorable direction to extend the mine may be predicted . Frequency distributions of assay residuals for uranium , vanadium , and lime are compared to frequency distributions of assays without regard to trend . Correlations among these variables are obtained and interpreted . The statistical methods employed illustrate certain techniques that may be used to analyze assay data from ore deposits in general .

Jan 1, 1964

By F. D. Everett

The exploration work on a seleniferous tuff deposit near Lysite, Wyo., was confined chiefly to an area of approximately 1 square mile selected on the basis of prior examination and sampling work by the Bureau of Mines. This area was superficially explored by digging and sampling over 2,000 feet of trenches and 15 test pits. The surface sampling indicated that the deposit might contain a multimillion-ton reserve of easy-to-mine volcanic tuff assaying more than 0.01 percent Se. Later, 11 holes, ranging in depth from 57 to 135 feet and totaling 929.4 feet, were drilled under contract using a dry rotary drill. Samples for assay were cut at 5-foot intervals or at noticeable physical changes in the formation being drilled. Of the 206 samples assayed from the drilling, only 8 contained more than 0.005 percent selenium, and 2 of these assayed as high as 0.012 percent Se. Chemical analyses of samples obtained from six holes drilled by the Nugget Coal & Timber Co. to the south of the area explored by the Bureau of Mines showed that no selenium-bearing formations were encountered in that work. Two of 72 samples taken from 42 validation pits dug by claim holders contained more than 0.005 percent selenium. The exploratory work established that the selenium mineralization is erratically distributed in small irregular bodies and is not confined to any one tuff bed. Because of the lack of correlation between the infrequent showing of low-grade tuff, neither the extent nor grade of the reserves could be calculated.

Jan 1, 1957

By A N. Danoucaras, S E. Goater, D Hearne, A M. Bansuan

It is globally recognised that existing and emerging mining activities should be conducted in a æsustainableÆ manner for the entire life of mine. Many companies annually publish corporate sustainability reports to demonstrate their actions in accordance with international expectations. This concept of sustainable mining practices also applies to mine water management, with influences often extending beyond site operations, affecting surrounding catchments and community users. This paper explores differences in conceptual and operational terms of æsustainableÆ mine water management within the Philippines. Outcomes of a review of corporate sustainability reports, governance documentation, research programs, and stakeholder knowledge acquired through action-research workshops are presented. The paper aims to inform and support future capacity building exercises delivered by the International Mining for Development Centre (IM4DC), with outcomes tailored to government officials and policy makers of developing countries. The project is funded by IM4DC, which is working with AusAID to identify needs and develop capacity with regard to mining for development; specifically, issues pertaining to governance and regulation, social and environmental sustainability, and operational effectiveness in developing countries.CITATION:Bansuan, A M, Goater, S E, Danoucaras, A N and Hearne, D, 2012. Integrated sustainable water management in mining for development in the Philippines, in Proceedings International Mine Management 2012, pp 205-226 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By A. Rios

ENAMl's Paipote Smelter commenced operations in 1951. At present, it processes 230,000 tonnes/year of green feed in a conventional smelter, which comprises one reverberatory furnace, two Hoboken, one Peirce-Smith converters and one rotary anode furnace. The feed is composed of 83% copper concentrate and 17% metallic copper precipitates, which results in a feed average grade of 32% of copper content. The final products are 75,000 tonnes/year of copper anodes and 48,000 tonnes/year of sulphuric acid. At present, the plant is undergoing a modernization to expand the smelter capacity to 300,000 tonnes/year of green feed and increase the sulphuric acid production to 100,000 tonnes/year. This will be achieved with the installation of an El Teniente Converter and an expansion in the acid plant. The work began in November 1991 and is scheduled to be in operaton by March 1993. The paper provides an overview of the modernization plans and results achieved to-date.

Jan 1, 1993

By H Arvidson, V Chamberlain, J Joughin, N Pollock, F Cessford, T Flitton, T Rowl

Environmental, social and governance issues (ESG) have become a defining feature in the marketplace to differentiate preferred investments. With the sustainability commitment and reporting landscape anticipated to evolve exponentially, it is now imperative to rapidly develop the approach taken by mineral companies to adequately identify and address ESG risks and opportunities in the reporting of Mineral Resource and Mineral Reserve (MRMR). MRMR cannot be effectively reported as technically and financially assured and realistically executable, if ESG is not integrated into the strategy, business model, input assumptions and process that defines and drives robust MRMR public reporting. Regulatory reporting codes across the globe are presently in various stages of being updated and modified to ensure ESG factors are appropriately covered as a key part of diligent and transparent disclosure. Security exchanges are making it clear that companies must not omit ESG risks from reports to investors. This paper discusses associated challenges for MRMR reporting and suggests avenues for improvement. Key themes include: the importance of procedure rather than prescription and checklists; how ESG criteria impact Modifying Factors and determination of Reasonable Prospects for Economic Extraction (RPEE); the need for financial models to account for material ESG commitments; the uniqueness of each mineral asset; the need for education, upskilling and accreditation of both ESG experts about MRMR reporting and equally Competent Persons in ESG matters; and the need for clear and balanced reports that meet the needs of end users. (RPEE is adopted here for simplicity and consistency, recognising that some reporting codes still include ‘Eventual’ in the term (ie RPEEE). Whilst RPEE and RPEEE are subtly different the intent is to point to the process of assessing ESG factors in determining reasonable prospects.) The principles of transparency, materiality and competence remain paramount when considering the impact of ESG matters on MRMR reporting, and this necessitates an inclusive, cohesive, and integrated approach to assessing ESG issues to ensure the necessary expertise and diligence is applied.

May 24, 2023

By Karina Forster

Rock mass characterisation is a critical component of effective stope design. Unexpected excessive stope dilution or uneconomic stope sizes can be the result of rock mass characterisation that is not representative of actual stope conditions. Comprehensive characterisation of the rock forming the stope hanging wall, back, ends and footwall is best done by a rock mechanics or ground control expert, however, this is time consuming and is often limited by available access. There are two general approaches for characterising a stope hanging wall for dilution estimating. Detailed classification and mapping data can be collected in local areas where good exposure is available. Personnel, exposure and time are usually not available to do a thorough analysis for all stopes. The stope hanging walls are then broken into lenses or domains and similar conditions are assumed for each area. The second approach consists of using readily available data such as RQD. Other rock mass properties which influence hanging wall behaviour are estimated based on back analysing a few case histories. Stope design is then based on the variability of the one parameter, such as RQD, that is consistently measured for the rock mass surrounding the ore body. This paper presents a third approach which looks, in depth, at the interpretation of geological core logging data for rock mass characterisation. Several rock mass properties that influence stope design, such as joint alteration, rock mass strength, joint spacing and orientations, have been linked to data collected by the mine geologists. This drill hole logging data was calibrated against underground mapping and used to back analyse the dilution prediction for mined-out stopes.

May 1, 2006

By Myles E. Robinson

Significant changes in the markets for coal have taken place since World War II, As used in this study the term ?coal? will refer to bituminous coal, The anthracite industry in size, characteristics, and problems differs materially from the bituminous coal industry, These changes have both influenced and been influenced by the mechanization of mines, and by decreased distribution costs, especially in transportation. It is the purpose of this paper to examine these post-war changes, to assess their impact upon the production and distribution of coal, and to explore future market developments in the light of past and present trends and relationships. The layman lacks adequate informatian on the production, demand, and distribution of coal. There are two reasons for this. First, there is a relative lack of statistics coveting the industry, Coal operators and distributors are not required to file with any government agency the type of much more complete statistics filed by the railroads and public utilities with national and State agencies. The Bureau of Mines assembles much useful information on the coal industry, but several areas, including that of investment and finance, have no central depository which can be used to keep the public informed of the nature and extent of the industry and its problems.

Jan 1, 1964

By K. Lascelles

ABSTRACT Nickel compounds vary significantly in their toxicological properties, so it is critical that continuing studies to accurately quantify worker exposures consider the processing that accompanies refining nickel-containing materials. The Clydach nickel refinery, which has operated for more than 100 years, was the first nickel-producing facility to show a high risk for lung and nasal-sinus cancers among workers employed since it opened in 1902. Process chemistry and equipment have changed dramatically over Clydach’s history. This paper describes the processing evolution at Clydach with a focus on the propensity for aerosol formation and the forms of nickel in airborne dusts.

Jan 1, 2013

By M Russ, J Gediga

This paper shows an economic feasible approach to implement greenhouse gas (GHG) reduction measures into the mining and metallurgy industry (MMI). The goal to improve energy consumption is directly linked to the reduction of GHG emissions in the MMI. A baseline scenario of the considered reference system and of the respective reference year has to be designed and analysed. In a second step an analysis of the same operation using the best available technology (BAT) processes is carried out to generate a basis for a benchmark system. The identified gaps will be reported and the potential GHG emission reductions will be put into relation to the investment, running cost and generated carbon credits of the new process technologies to be implemented. This economic feasibility calculation is necessary to realise a cost efficient GHG reduction roadmap decision-making for implementing new technology into the companyÆs business operations. The GHG reduction roadmap is developed using the marginal abatement curve approach.

Jan 1, 2009

By Brent C. Jellicoe, Phil Robertshaw, J. Murphy, Peter Williamson

Kimberlites and associated diamonds have been the focus of extensive exploration in central Saskatchewan since 1988. During 1989, Uranerz Exploration and Mining Limited identified 71 shallow magnetic anomalies in the Fort a la Corne area from detailed aeromagnetic surveys. By the end of 1991, 18 of these targets had been proven, by drilling, to be kimberlite bodies encased within Cretaceous sedimentary strata. From 1991 to 1997, the number of drill-confirmed kimberlite bodies increased to 69. Our current view, drawing on an integration of geophysical and geological information, is that the kimberlites are composed of individual bodies and multi-vent clusters of coalesced bodies, all apparently constructed of stacked, temporally distinct layers of pyroclastic crater-facies kimberlite. Diamond recoveries and geochemical results from associated heavy minerals at Fort a la Corne remain highly variable, although continued minibulk sampling is expected to improve the estimation of diamond grades for the most prospective bodies.

Jan 1, 2001

By T. D. MacQueen

Thank you Mr. Stevens. It's a pleasure for me to be speaking to this meeting of the Society of Mining Engineers of AIME this afternoon, and the Gypsum, Association is grateful for the invitation. A brief word about who we are: the Gypsum Association is the trade association for the gypsum industry - the manufacturers of gypsum board and lath a-d plaster. We have a membership of eight companies. These eight companies produce about 90% of the gypsum products manufactured in the United States ... closer to 94% actually. Our headquarters is in Evanston, Illinois. We have an east coast office in Washington, D.C. where the eastern manager handles technical and building code matters and maintains liaison between all of the government agencies and departments and our industry. We also have a west coast office in Los Angeles where our west coast representatives is heavily involved with the Uniform Building Code and ICBO. And then in the Evanston office our manager of technical and building code services, Herb Carlsen, bites his nails and loses his hair over these problems and various other projects that come in, such as conversion to metric and various other things. We also have a research associate at the National Bureau of Standards in Washington who is currently concentrating his efforts on the combustibility of building materials. His studies involve current testing methods, definitions, data analysis, and proposed new testing methods,.' It is anticipated that this program will lead to a better understanding of non-combustibility of building materials and systems. I mentioned that our members represent over 90% of gypsum products,' manufactured in the United States; it might be well to point out a couple of statistics about what that really means. According to the Bureau of Mines,

Jan 1, 1977

By C. C. Hustwit

The U.S. Bureau of Mines formulated a new mathematical model to characterize iron oxidation. The new model is intended to replace the currently used model, recommended by the Environmental Protection Agency (EPA), for most acid mine drainage (AMD) treatment applications. The new model was evaluated in a series of five synthetic AMD treatment tests. The initial ferrous iron concentrations ranged from 800 to 2,400 mg/L. In these tests, the Bureau model underpredicted the measured ferrous iron oxidation rates by a range of 3.24 to 8.03 pct. This was considered to be in close agreement after consideration of experimental error. The model proposed by the EPA was also evaluated using the same test data. The EPA model underpredicted the oxidation rates by a range of 77 to 100 pct in four tests and overpredicted by 19 pct in one test. The model formulated by the Bureau expresses that the rate of iron oxidation is a function of a treatment system's oxygen transfer efficiency and is independent of ferrous iron concentration when treated to near-neutral pH's. A new test method for evaluating oxygen transfer in flow-through reactors is also described.

Jan 1, 2010

By Jean-Louis Robert

Field work inaugurated in 1962 in the townships of Lemieux and Lesseps, in the Gaspe Peninsula of Quebec, has permitted the author to delineate the lithologic units of the area, to elucidate a few stratigraphic problems and to outline several zones of alteration. Certain features of these zones and the numerous mineralized showings in the area merit the attention of prospectors and exploration companies.

Jan 1, 1966

By C. Özgen Karacan

Methane emissions from the active face areas and from the fractured formations overlying the mined coalbed can affect safety and productivity in longwall mines. Since ventilation alone may not be sufficient to control the methane levels on a longwall operation, gob vent boreholes (GVB), horizontal and vertical drainage boreholes, and their combinations are drilled and used as supplementary methane control measures in many mines. However, in most cases, the types of degasification wellbores chosen are decided based on previous experiences without analyzing the different factors that may affect this decision. This study describes the development of an expert classification system used as a decision tool. It was built using a multilayer perceptron (MLP) type artificial neural network (ANN) structure. The ANN was trained using different geographical locations, longwall operation parameters, and coalbed characteristics as input and was tested to classify the output into four different selections, which are actual degasification designs that US longwall mines utilize. The ANN network selected no degasification, GVB, horizontal and GVB, and horizontal, vertical and GVB options with high accuracy. The results suggest that the model can be used as a decision tool for degasification system selection using site- and mine-specific conditions. Such a model can also be used as a screening tool to decide which degasification design should be investigated in detail with more complex numerical techniques.

Jan 1, 2009

By James R. Kerr

Although metallurgical benefits of processing metals in a vacuum or reduced atmosphere have been realized for a hundred years, the problem of creating a vacuum in the range from 10-0 to 10-4 mm. of mercury in a moderately sized furnace chamber has been difficult to solve. The demand for these and lower pressures, with the advent of World War II, for separating the fission-able uranium isotope from its stable twin by the electromagnetic process, gave impetus to developing pumps capable of delivering extremely low pressures. With the release of data by the Atomic Energy Commission on methods of securing high vacuum in large equipment, steel companies took the initiative, and the growth of the vacuum-melting industry was assured. Vacuum-induction melting of steel in the United States began on a small scale in early 1945 and in 10 years grew to 60,000 pounds per month or 720,000 pounds per year. The years following 1954 showed tremendous expansion, culminating in 1958 in a capacity of more than 36 million pounds.

Jan 1, 1962

By Steven Norris, William Moler, Michael Cole, Patrick Doig, Debi Lewis, Craig Pyle, Matthew Crow

The recently completed Lower Northwest Interceptor Program (LNWI) in Sacramento, California comprises, ten pairs of micro tunnels totaling 4,369 m (14,417 ft),three horizontal directionally drilled bores totaling 956 m (3,154 ft), and two large diameter tunnels under the Sacramento River totaling 1,198 m (3,953 ft). This paper briefly summarizes surface and subsurface conditions, and planning and design considerations. It then goes on to describe problems encounterd with each trenchless crossing, as well as lessons learned with respect to shaft construction, ground control at shafts during tunnel break-in and break-out, frac-out and heave, settlement, obstructions, coordination with permitting agencies, and application of geotechnical baseline reports.

Jan 1, 2007

By F. N. Siddiquie, Mohd Shaif, Rajiullah Khan, Juned Alam

Manganese ore bodies of Banswara Mn belt were classified into stratiform and stratabound types, based on their mode of occurrence, distribution, and their chemical characters. These ore bodies generally composed of braunite, pyrolusite, cryptomelane/ psilomelane, wad, etc. The stratiform-type Mn ore bodies are conformable with the associated host rocks (Mn phyllite, etc.) and occurred in the form of layers, bands, etc., which are variable in their shape and size. These ore bodies are also strongly folded with the enclosing host rocks. The others, which are stratabound-type Mn ore bodies, also showed an intimate association with the associated host rocks. These types of ore bodies occurred in thin layers, pockets, lenses, stringers, etc. The classified ore bodies are confined with Kalinjara formation of Aravalli Supergroup of Paleoproterozoic age. The ore bodies are structurally controlled and well associated with phyllite, schist, limestone, quartzite, etc. The stratiform-type ore bodies constitute a marginal to low Mn grade and are also characterized by lower Mn content (26.19–39.24%) along with the Mn/Fe ratio of 7.16–12.23, while the stratabound-type Mn ore bodies are rich in Mn (35.92–49.64%) along with the higher Mn/Fe ratio of 14.15–23.97. However, the poor Mn grade along with high siliceous impurities of Banswara Mn deposits is subjected to them for intermittent mining activities in the past and, consequently, did not attract the scientific and industrial community for the evaluation of these resources. Therefore, the authors attempted this study in a scientific and systematic manner (mode of occurrence/distribution and possible methods for evaluation/exploration) to evaluate the potential of existed and newer Mn deposit resources in the Banswara Mn belt. The whole findings would be very much helpful for exploration/ mining geologist along with other concerned, to completely evaluate these Mn deposits in the future.

Aug 16, 2021

By John Reilly

Costs of complex/underground projects have been consistently underestimated and delivery on time and on budget has been problematic. This has been attributed, to inadequate cost estimates and unidentified and/or insufficiently managed risk. Use of probabilistic cost estimates like the Washington State Department of Transportation?s CEVP® process (developed by the author and others) has produced more realistic cost estimates, explicitly identified and quantified risk (as input to risk management plans) and early awareness of key project issues. This paper updates previous work (NAT 2004), adds implementation detail for probalistic cost estimating as used by WSDOT, FHWA and other agencies and will address key issues in risk management, as related to probalistic cost estimates.

Jan 1, 2008